Gentlefolk,

The biggest bang on the 4th of July this year WON’T be coming from the U.S. It will be a bit further away – about 83 million miles or so.

NASA’s Deep Impact spacecraft has launched an “impactor”, which should crash into the comet Tempel 1 in the wee hours of the morning. I use the word crash loosely; that bad boy’s impact is expected to excavate a crater more than 25m deep and 100m across. An explosive impact of about 4.5 tons of TNT. I hope that NASA has better luck at hitting this target than some other space interceptor programs do.

All the big optical telescopes are trained on the comet to record, and later measure, what comes out of the explosion. The Deep Impact spacecraft itself will be taking photos of the event.

Inevitably, it seems, there are some who are protesting that NASA shouldn’t do this!

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Eudaimonia